THE POWER OF SLEEP

Often in sport, people search for those 'marginal' gains that may help performance but neglect some fundamental basics. Nigel Mitchell, Performance Nutritionist, discusses how having sufficient good-quality sleep is critical for recovery and performance.

Those of us with young children will understand how a lack of sleep affects us both emotionally and physically. Chronic sleep deprivation, such as 2-4 hours a night over a two-week period, will affect performance in the same way as going without sleep for 24 hours.

Why do we sleep?

Sleep is the body's way of resetting and re-establishing the equilibrium. This is from a metabolic, hormonal and nervous system perspective. As with most things, we are all individual and require different amounts of sleep to function optimally, but most people have a good idea of how much sleep they require. A good guideline for healthy adults is between 7 and 9 hours of sleep per night.

Are you getting enough sleep?

If you normally fall asleep within 20 minutes of going to bed and wake up naturally in the morning feeling refreshed, then you're probably getting enough sleep. But if you find that you struggle to get to sleep and have restless nights, then paying attention to your sleep hygiene may help. Often athletes find that they sleep perfectly well most of the time, but during competition, when nerves start to set in, their sleep becomes disrupted.

In my experience working with professional athletes, sleep is a topic that is often high on the agenda, and specifically the role that nutrition can play in aiding sleep. There are a growing number of products that are designed to help support sleep, including pillows, eye patches, lamps and nutrition supplements. However, before we look at how we can improve sleep, it's important to understand the things we do that can have a negative impact.

Sleep hygiene

Our sleep habits are often referred to as sleep hygiene. Many good sleep hygiene habits may seem like common sense, but it is surprising how often athletes overlook this and make simple mistakes that have a detrimental impact on the quality of their sleep. Below are some steps you can take to improve your sleep hygiene:

• Create a regular bed-time routine. We are creatures of habit, and having a routine helps to prepare the mind and body for sleep.
• Avoid loud noises, as these stimulate our sympathetic nervous system – our fight or flight response.
• Reduce light exposure before bed. Melatonin is a hormone that is produced by the pineal gland and is believed to regulate sleep. It is produced from amino acids such as tryptophan. Darkness acts as a stimulant for the production of melatonin, and light reduces the body's production.
• Switch off your tablet or computer. Alertness is stimulated mainly by light in the blue spectrum. Many tablets and computers now have settings that reduce this light. Special glasses have also been developed that cut out the blue light.
• Consider an eye mask. People often report that they wake up earlier in the summer months due to the early sunrise.
• Avoid alcohol. Many people feel that some alcohol can help with sleep, but in fact for most it reduces sleep quality.
• Avoid caffeine after 2pm. Many athletes consume a lot of caffeine, in the form of tea, coffee and 'energy' products such as caffeinated gels and drinks. Caffeine can have a negative impact on sleep, probably because of the stimulation of the nervous system along with its diuretic effect.
• Emotional stress can affect our sleep. Some people find practising mindfulness can help.

How can nutrition help?

There is not a great deal of scientific evidence behind the positive impact of nutrition on sleep, but the anecdotal evidence from athletes and members of the general population is extremely convincing. Although there is no doubt that some effects may be down to placebo, I have personally seen positive results when implementing the following nutrition interventions with the athletes I work with:

• A bedtime cup of chamomile tea and honey. Chamomile tea has long been used as a 'calmer' and relaxer. Honey is high in fructose, which helps to maintain the liver glycogen, which can get depleted overnight while you sleep.
• The supplement 5-HTP (5-Hydroxytryptophan) is becoming a very popular nutritional sleep aid. It is used in the body's production of serotonin and melatonin. There are few contraindications with 5-HTP, such as avoiding using it if an individual is also on anti-depressants.
• Cherry juice (Montmorency), such as Healthspan Elite Performance Cherry, contains melatonin. Many athletes have found this useful in helping with sleep.
• Taking zinc and magnesium at night is often used to support sleep.
• Casein protein: this comes from the old wives' tale about a hot milky drink before bed. But actually having some casein (slow digested protein) can help some people with sleep, and can have the added benefit of providing amino acids to the body, which can support muscle recovery.

People are becoming more aware of the importance of sleep, and this is never more true than for athletes. If you are concerned about your sleep, some of the information provided here may be useful. Modern technology is also helping to provide support around sleep, and many fitness watches and trackers can provide quantifiable data on the quantity and quality of your sleep.

There are many factors that can affect sleep. If you are someone who suffers from poor sleep, try making some of the changes suggested above. You will no doubt see an improvement in your sleep and performance.